From 25687c269780e2c3a6375eebc362249bfeabadd9 Mon Sep 17 00:00:00 2001
From: Yu Zhang <yuzhangyu@fb.com>
Date: Thu, 15 Jun 2023 09:56:14 -0700
Subject: [PATCH] Make the error message safer

---
 env/env_posix.cc | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/env/env_posix.cc b/env/env_posix.cc
index 400b8ac6ee0..ae2f9036028 100644
--- a/env/env_posix.cc
+++ b/env/env_posix.cc
@@ -330,12 +330,16 @@ class PosixEnv : public CompositeEnv {
   }
 
   Status GetHostName(char* name, uint64_t len) override {
-    int ret = gethostname(name, static_cast<size_t>(len));
+    const size_t max_len = static_cast<size_t>(len);
+    int ret = gethostname(name, max_len);
     if (ret < 0) {
       if (errno == EFAULT || errno == EINVAL) {
         return Status::InvalidArgument(errnoStr(errno).c_str());
+      } else if (errno == ENAMETOOLONG) {
+        return IOError("GetHostName", std::string(name, strnlen(name, max_len)),
+                       errno);
       } else {
-        return IOError("GetHostName", name, errno);
+        return IOError("GetHostName", "", errno);
       }
     }
     return Status::OK();